"I am a victim of political conspiracy. Mamata Banerjee has already spoken on this," Mitra told reporters after coming out of Alipur court where he was produced by CBI this afternoon.

The Transport and Sports Minister was remanded to four days in CBI custody by the court.

The court premises was fortified with deployment of a large number of police personnel and both its gates were closed.

Thousands of Trinamool Congress supporters, mostly from Kamarhati, the assembly constituency he represents, squatted in front of one the gates, shouted slogans and displayed placards in a show support to Mitra.

They also burnt an effigy of Prime Minister Narendra Modi and tore his pictures.

After the verdict, they stayed put in front of the gate waiting for Mitra and the police had a trying time to find a safe passage for Mitra's car.

TMC supporters clung to the roofrails of the vehicle on both sides and banged the glass windows which had been rolled up.

CBI investigating officer F B Karna sat beside Mitra.

The police managed to disperse them soon but the traffic in front of the court complex was thrown out of gear.